Behavior
It is a highly gregarious species in autumn and winter. Flock size is highly variable, with huge flocks providing a spectacular sight and sound usually occurring near roosts. These huge flocks often attract birds of prey such as Merlins or Sparrowhawks. Flocks form a tight sphere-like formation in flight, frequently expanding and contracting and changing shape, seemingly without any sort of leader. Very large roosts, exceptionally up to 1.5 million birds, can form in city centres, woodlands, or reedbeds, causing problems with their droppings.
Flocks of anything from five to fifty thousand Starlings form in areas of the UK just before sunset during mid winter. These flocks are commonly called a Starling "Moot".